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We have succeeded in synthesizing organic biradical crystals of \(m\)-Ph-V2 [= 1,3-bis-(1,5-diphenylverdazyl-3-yl)benzene]. The intra and intermolecular interactions, which are deduced from the molecular packing in the crystal, are considered to form an alternating double chain. We evaluated the intramolecular ferromagnetic (FM) interaction from an analysis of the magnetic susceptibility of isolated \(m\)-Ph-V2 molecules. We analyzed the magnetic susceptibility and magnetization curves of the crystals by the quantum Monte Carlo method and successfully explained these properties using an \(S = 1/2\) FM alternating double chain model, which consists of antiferromagnetically coupled FM alternating chains. In addition, the magnetic susceptibility and specific heat showed anomalous behavior at \(T_{\text{N}} = 1.9\) K, which indicates the magnetic phase transition to an antiferromagnetically ordered state.

We have successfully synthesized new organic radical crystals of 2-Cl-6-F-V [= 3-(2-chloro-6-fluorophenyl)-1,5-diphenylverdazyl]. Two types of dominant intermolecular interactions forming a honeycomb lattice are deduced from the molecular packing in the crystal, and ab initio molecular orbital calculation also indicate such an exchange network. We analyzed the magnetic and thermodynamic properties by using the quantum Monte Carlo method and successfully explained these properties as an \(S = 1/2\) Heisenberg honeycomb lattice with ferromagnetic chain interactions. Our results indicate that 2-Cl-6-F-V is one of the few examples of a purely organic radical compound that forms two-dimensional lattices, and this paper presents the first complete, quantitative description of an actual honeycomb lattice material.

We report the magnetization process on the S =1/2 antiferromagnetic Heisenberg chain [PM·Cu(NO 3 ) 2 ·(H 2 O) 2 ] n (PM=pyrimidine). It has become clear that the staggered magnetic field plays an important role in the magnetic behavior from magnetic susceptibility and specific heat studies on single-crystalline samples. The magnetization curve for a single crystal of [PM·Cu(NO 3 ) 2 ·(H 2 O) 2 ] n does not show a divergent slope, but rounding behavior at the saturation field due to the effect of the staggered magnetic field even at 100 mK.

We have made magnetization measurements under pulsed magnetic fields on a S= 1 2 kagom e antiferromagnet [Cu3(titmb)2(OCOCH3)6] ·H2O. A magnetization plateau with one-third of the saturation moment has been observed in a certain range of field sweep rates at 100 mK . This transient phenomenon of the magnetization is analyzed using an exact diagonalization method and found to be due to the meta-stable states originating from frustration.

We have succeeded in synthesizing verdazyl biradical crystal of p-BIP-V2[=4,4·-·bis(1,5-diphenylverdazyl-3-yl)biphenyl]. The magnetic susceptibility and specific heat showed anomalous behavior at 7.5 K, which indicates the magnetic phase transition to an antiferromagnetic long-range order. Considering the sufficient development of short-range magnetic order expected from the specific heat and the almost linear field dependence of magnetization below 7.5 K, we have confirmed that p-BIP-V2 has strong two-dimensional magnetic interactions.

The crystal structure and magnetic properties of metaphenylenebisverdazyl biradical (m-Ph-V2) are presented. The temperature dependence of the product of the magnetic susceptibility and temperature, which is proportional to the square of the effective magnetic moment, shows a round maximum at about 40 K and a stationary behaviour at half the value of the room temperature in the temperature range of 4–7 K In the crystal structure, the dimeric structure of molecules is noticeable and the susceptibility data were analysed by the four-spin cluster model with an S = 1/2. The intrarmolecular ferromagnetic interaction was estimated to J1/kB = −40 K.

In this paper, we present the magnetic properties of 2b3CuCl22H2O (b = betaine, C5H11NO2). 2b3CuCl22H2O is the first model substance for a two-dimensional S = 1/2 orthogonal antiferromagnetic trimer system. We have performed magnetic susceptibility, magnetization curve, and specific heat under extreme conditions: low temperatures and high magnetic fields in this system. The experimental results indicate that this substance is a magnetically S = 1/2 antiferromagnetic trimer system. The magnetization also shows one-third of the saturation value (MS ~ 3.2μB/f.u.) between 5 and 14T The specific heat in a zero field shows a sharp peak at 1.38K corresponding to a long-range magnetic ordering, TN. As the magnetic field increases, the TN shifts remarkably to a lower temperature and is suppressed. Above 5T, the specific heat has no anomaly down to 150mK In the plateau region with an energy gap, the magnetic ordering seems to be disappeared.

At 4.2 K , the coercive field of Ni film on GaAs (0 0 1) was five times larger than that of Ni/Si (0 0 1). Because of these findings, a multilayer, Ni/Si/Ni/GaAs was prepared and its magnetization process was studied in a temperature range from 1.8 to 360 K . At temperatures below 250 K , an antiparallel spin state was observed, the degree of which was highest at 1.8 K . The bottom Ni layer was observed to be totally influenced by the underneath GaAs but not by the Si.

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We synthesized single crystals of NH4CuPO4 H2O by a chemical reaction in aqueous solutions. Magnetization and specific heat are well reproduced by a dimer model, and NH4CuPO4 H2O does not show any field-induced magnetic phase transitions. The interdimer interactions would be too weak to observe field-induced phase transitions.

We have investigated the high field magnetization of La 1- x Sr x CoO 3 for x ≤0.05 up to µ 0 H ext = 67 T. In a dilute limit, about 30 nonmagnetic Co ions of two species (Co I and Co II in LaCoO 3 ) are converted to magnetic Co ions (Co III ) by introducing one Sr 2+ , leaving the remaining Co I and Co II little affected by the Sr doping. This finding shows that a new spin-phase separation with three Co species appears by the Sr doping. The Co III ions form a magnetic cluster with a net magnetization several times smaller than that expected from the ferromagnetic aligned full moment. A spin-glass freezing appears below T g = 10 and 18 K for x = 0.03 and 0.05, respectively, in a weak magnetic field of 2 mT. In µ 0 H ext ≥10 T, however, the magnetization of Co III for 0.01 ≤ x ≤0.05, as a function of temperature and H ext , is almost independent of x after normalization with the Co III population. It means that the magnetic correlation among Co III within the cluster is robust against H ext , but the magne...

Cu3(OH)4MO4, which is a natural mineral szenicsite, has been studied by the magnetic susceptibility, the specific heat, and the high field magnetization measurement. This compound consists of S = 1/2 triple-chain of the edge-sharing octahedra CuO6. On the basis of the crystal structure in szenicsite, spin frustration can strongly affect the ground state. The magnetic susceptibility has a broad maximum around 80 K, which is characteristic of the quasi-one-dimensional antiferromagnet. There are no sign of magnetic phase transitions from 300 K down to 2 K in our measurements. The magnetization curve measurement up to 48 T at 1.3 K indicates that neither magnetic order nor spin gap is present. Assuming the triple-chains as the isolated uniform chains, we estimated the dominant exchange interaction J/kB = −66 K.

We find Cu2(AsO4)(OH)·3H2O (euchroite) is a model compound for the frustrated delta chain which is composed of corner-shairng triangles. Magnetic susceptibility, specific heat, high field magnetization and 1H-NMR measurements are carried out using natural mineral samples of euchroite to study magnetic properties. Large spin gap of about 100 K are shown to be presented in this compound.

The development of synapses was confirmed in the primary cultures of dissociated cerebral cortex neurons from chick embryos. Whole-cell patch clamp recording applied to dissociated neurons from 6- to 12-day-old embryos revealed that these neurons form functional synapses. In these cultures, both excitatory and inhibitory postsynaptic responses were observed. Synaptogenesis in our cultures seemed to be in proportion to the embryonic equivalent days, which are the sum of the days in incubation and culture.

A high-speed polarizing microscope system combined with a 37 T pulse magnet has been developed. This system was applied to successfully visualize the field-induced collapse of charge-orbital ordering in a layered manganite La(1/2)Sr(3/2)MnO(4). Quantitative analyses of the obtained polarizing microscope images provided clear evidence of this transition in contrast to rather moderate changes in magnetization and magnetoresistance. The ability of this system to carry out quantitative analysis was further tested through the observation of Faraday rotation in a Tb(3)Ga(5)O(12) crystal. The Verdet constant determined from the polarizing images is in reasonable agreement with that in literature. Local intensity analyses of the images indicate that we can investigate magneto-optical signals within an accuracy of 0.85% in an area of 9.6 x 9.6 microm(2).

High-field magnetization measurements have been performed at various temperatures on the molecular oxygen adsorbed in a microporous coordination polymer CPL-1. Molecular oxygen with S = 1 forms O2-O2 dimer in the nanochannels of CPL-1. The magnetic properties can be explained by not the S = 1 Heisenberg antiferromagnetic dimer model but the O2-O2 dimer model taking into account the spin-dependent intermolecular potential. This feature is attributed to the fact that the magnetic interaction between O2 is comparable to the van der Waals force.

We report here the results of 51V-NMR experiments as well as susceptibility and high-filed magnetization measurements on a spin-1/2 honeycomb lattice antiferromagnet InCu2/3V1/3O3. The magnetization curve at 4.2 K showed no anomaly up to 54 T. A small anomaly around 38 K was found in the nuclear spin-latteice relaxation rate T−11 as well as the susceptibility, while NMR spectrum was temperature independent. Further, T−11 showed a broad maximum around 15 K and a tendency to be constant towards the lowest temperature of 2 K. Our results suggest that a large spin fluctuation remains until 2 K without a specific magnetic long-range ordering. Preliminary NMR results for an oriented sample are also shown.

The magnetization of LaCoO 3 shows a magnetic transition induced by level crossing at a magnetic field of 60 T below 25 K, which is consistent with the energy diagram determined from electron spin resonance experiments. However, the amount of Co ions with g = 3.35 contributing to the magnetic transition is sample-dependent and at most 14% of the total Co ions in LaCoO 3 . We found that the rest of the Co ions also contribute to the magnetization, which is a maximum at around 100 K. We analyzed the magnetization assuming two kinds of Co species, Co I and Co II , both of which have the nonmagnetic ground state. The energies and the g values of the magnetic excited states are 135 K and 3.35 for Co I , and 250–260 K and 1.9–2.0 for Co II , respectively. Co I ions are suggested to be associated with oxygen vacancies and the surface of LaCoO 3 .

Magnetic properties of the spin-1/2 kagome-like compound volborthite are studied using a high-quality polycrystalline sample. It is evidenced from magnetization and specific heat measurements that the spins on the kagome lattice still fluctuate at low temperature, down to T = 60 mK that corresponds to 1/1500 of the nearest-neighbor antiferromagnetic interaction, exhibiting neither a conventional long-range order nor a spin gap. In contrast, 51V NMR experiments revealed a sharp peak at 1 K in relaxation rate, which indicates that a certain exotic order occurs. Surprisingly, we have observed three "steps" in magnetization as a function of magnetic field, suggesting that at least four liquid-like or other quantum states exist under magnetic fields., Comment: J. Phys. Soc. Jpn, Vol.78, No.4 (2009), in press

A divalent lithium salt Li 2 B 12 F 12 dissolved in propylene carbonate (PC) with four different concentrations was studied by NMR methods and ionic conductivity. The individual diffusion coefficients were measured by 1 H, 7 Li, and 19 F pulsed-gradient spin-echo NMR for the solvent PC (D PC ), lithium (D Li ), and anion (D anion ). Because two-step salt dissociation processes can be assumed for the divalent Li 2 B 12 F 12 , the existence of LiB 12 F - 12 in addition to Li + and B 12 F 2- 12 must be taken into account. The comparison was made with the diffusion coefficients of LiPF 6 in PC. The plots of ion diffusion coefficients vs solvent diffusion coefficient were linear for both Li 2 B 12 F 12 and LiPF 6 PC in solutions. Although the PF 6 diffusion is much faster than lithium diffusion for the LiPF 6 in PC, the D Li and Danion of the Li 2 B 12 F 12 have similar values in the temperature range measured for the four different salt concentrations. The experimental parameters R Li = D Li /D PC and R anion = D anion/ D PC calculated from the individual diffusion coefficients suggest that the PC solvation around B 12 F 12 can be assumed in addition to the PC solvation around Li. Tentatively, the Nernst-Einstein ionic conductivities σ NE were calculated from the D Li and D anion under the assumption of the complete ion dissociation. The temperature- and concentration-dependent behaviors resemble those of the ionic conductivity σ ac observed by the electrochemical ac method.

Keratin expression was studied immunohistochemically in 27 ameloblastomas using polyclonal antibody against wide-spectrum keratins (TTL) and monoclonal antibodies against lower- and higher-molecular-weight keratins (PKK1 and KL1), respectively, to clarify the tumor differentiation. Reactions with TTL and KL1 antibodies were generally positive in the stellate cells of the follicular or acanthomatous ameloblastomas. Cell nests of the basal cell type were positive for PKK1. On the other hand, the reactions with TTL or KL1 in the plexiform type were generally weak or absent. From these facts, it was concluded that the follicular, as well as acanthomatous, ameloblastoma is liable to undergo squamous differentiation, whereas the plexiform ameloblastoma remains in primitive stage of tumor differentiation.

The transverse and longitudinal magnetostrictions of LaCoO 3 have been measured in pulsed magnetic fields of up to 35 T in the temperature range between 4.2 and 300 K. The magnetostrictions are pro...

We have performed magnetic susceptibility and low and high field magnetization measurements on single crystals of the Ni tetramer compound [Ni4(μ-CO3)2(aetpy)8] (ClO4)4 (aetpy = 2-aminoethyl-pyridine) with a butterfly (diamond) structure. We observed a two-step-like magnetization curve and a further increase of magnetization around 63 T in magnetic fields up to 68 T perpendicular to the Ni tetramer plane (c-axis). From the magnetic fields at steep jumps of the magnetization, we determine broadly the short diagonal (J1) and the side (J2) antiferromagnetic exchange constants between the Ni ions (J1/kB = 41.9 K and J2/kB = 9.2 K) in this compound. The long diagonal exchange interaction (J3) is ferromagnetic and the exchange constant is evaluated as J3/kB = −0.66± 0.04 K from the comparison between the magnetization measured in steady fields at 2 K and the calculated one. The origin of hysteresis of the magnetization in pulsed magnetic fields is discussed based on the calculated energy diagram.

The hardness, transverse-rupture strength (TRS), deformability, etc. of TiC0.7N0.3-and TiC0.5N0.5-MPo alloys vacuum-sintered and then HIP-treated were studied mainly in the temperature range from 1073 K to 1273 K, comparing with those of Ti(C, N)-Mo2C-Ni alloys.The decrease in the hardness and TRS of Mo bonded alloys with increasing test temperature was markedly suppressed. The alloys containing 20-40 vo1%Mo showed at 1273 K the values of hardness and TRS as high as 600-800 Hv and 0.9-1.2 GPa, respectively, with a extremely high resistance to deformation. Therefore, the Mo bonded alloys were considered to be of importance for the special tool materials, when coated with the layer having high resistance to oxidation.

TiC, Ti(C, N) and TiN layers were coated by PVD (ion plating) process at 573-853 K on HIP-treated WC-10%Co substrates, after the surface of substrate was ground or polished. The transverse-rupture strength (TRS) of specimens at room temperature and the adhesion between the layer and the substrate were mainly studied.The TRS of each coated specimen decreased with increasing PVD temperature. The surface state of substrate (ground or polished) did not affect the strength of each coated specimen. The specimens fractured from the coated layer, when PVD temperature was over about 773 K. However, the specimens coated at lower temperatures than 773 K were apt to fracture from the inside of substrate with no decrease in TRS. Annealing treatments of the coated specimens caused the decrease in TRS, the strength decrease being larger with decreasing PVD temperature. The results of strength tests showed that sufficient adhesion appeared to be obtained between the layer and substrate independently of PVD temperature, sort of coated layers and substrate surface-state. However, according to the results of cutting and scratch tests, the adhesion of coated layer to the ground substrate appeared to be inferior to that to the polished substrate. This was attributed to the fact that the surface of substrate changed in its quality during grinding by diamond wheel.

A case report is made of a hemangioma occuring in the parotid gland of 67-year-old woman. Patient complained of a gradually increasing swelling in the preauricular area. She was referred by her dentist. Paralysis of the facial nerve was not observed. In the radiographic examination. The posterior edge of the ascending ramus was found to be absorbed. Salivary imaging by means of 99mTc scintigraphy showed a cold lesion in the parotid gland. 67Ga scintigraphy showed normal appearance. Sialography of the parotid gland revealed typical ball-in-hand appearance. From these findings, a clinical diagnosis of benign salivaly gland tumor was made. The tumor was removed by total parotidectomy with all branches of the facial erve reserved. The tumor was present in the deep portion of the gland the histopathological diagnosis was cavernous hemangioma. Facial paralysis was observed postoperatively but disappeared within six months. Recurrence has not been observed over the past two years.

ラット皮膚由来の線維芽細胞を用いて, 細胞増殖とコラゲン線維形成に対する培地, 血清濃度, アスコルビン酸とジフェニルヒダントイン (DPH) の影響を形態学的に研究した。細胞増殖率は, α-MEM培地とDM-160培地で共に, 血清濃度依存性を示した。しかし, α-MEM培地での増殖率は, DM-160培地のものより高かった。α-MEM培地では, 線維芽細胞は培養1日で渡銀される線維を形成し, 増殖対数期と定常期を通して細胞外にコラゲン線維を形成・蓄積した。DM-160培地での線維形成率は培養3週まで低く, その後, コラゲン線維量の増加がみられた。DM-160培地 (アスコルビン酸含有量1μg/ml) の線維芽細胞は, α-MEM培地 (アスコルビン酸含有量50μg/ml) の細胞に比べて, アスコルビン酸欠乏状態であった。これらアスコルビン酸欠乏状態では, 典型的な64nm横紋を持つコラゲン線維形成は阻害され, 横紋のない, 細線維とmicrofibrilsが形成されていた。これらの結果は, この線維芽細胞はコラゲン線維形成にアスコルビン酸を必要とすることを明らかにした。培養線維芽細胞へのDPHの添加は, 細胞増殖とコラゲン線維形成の両都を促進した。